Light fixture for indoor grow application and components thereof

ABSTRACT

A light fixture includes a housing, and a lighting module. The housing defines first and second portions. The second portion defines a window. The lighting module is at least partially disposed in the second portion. The lighting module includes a submount, a plurality of light emitting diodes, a lens cover, and an encapsulating material. The plurality of light emitting diodes is coupled with the submount and is configured to project light through the window. The lens cover includes an exterior surface and overlies the plurality of light emitting diodes and the submount such that the lens cover and the submount define an interior therebetween. The encapsulating material substantially fills the interior.

REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.17/314,049, entitled Light Fixture for Indoor Grow Application includingHousing that Defines a Passageway, filed May 7, 2021 which is acontinuation of U.S. patent application Ser. No. 16/820,090, entitledLight Fixture for Indoor Grow Application and Components Thereof, filedMar. 16, 2020 and hereby incorporates these patent applications byreference herein in their respective entireties.

TECHNICAL FIELD

The apparatus described below generally relates to a light fixture thatincludes an array of light sources for illuminating an indoor growfacility. Each light source includes a light emitting diode (LED), alens, an encapsulating material that substantially fills the lens, and aprotective coating provided over an exterior surface of the lens.

BACKGROUND

Indoor grow facilities, such as greenhouses, include light fixtures thatprovide artificial lighting to plants for encouraging growth. Each ofthese light fixtures typically includes a plurality of LEDs thatgenerate the artificial light for the plants. The environment insidethese indoor grow facilities, however, can include different types ofgasses and/or airborne fluid particles that cause the optical quality ofthe LEDs to degrade (e.g., yellow) over time.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments will become better understood with regard to thefollowing description, appended claims and accompanying drawingswherein:

FIG. 1 is an upper isometric view depicting a light fixture, inaccordance with one embodiment;

FIG. 2 is a lower isometric view of the light fixture of FIG. 1 ;

FIG. 3 is a partially exploded upper isometric view of the LED lightfixture of FIG. 1 ;

FIG. 4 is a partially exploded lower isometric view of the LED lightfixture of FIG. 1 ;

FIG. 5 is a cross-sectional view taken along the line 5-5 in FIG. 4 ;and

FIG. 6 is a schematic view of various components of the light fixture ofFIG. 1 .

DETAILED DESCRIPTION

Embodiments are hereinafter described in detail in connection with theviews and examples of FIGS. 1-6 , wherein like numbers indicate the sameor corresponding elements throughout the views. A light fixture 20 foran indoor grow facility (e.g., a greenhouse) is generally depicted inFIGS. 1 and 2 and can include a housing 22, first and second lightingmodules 24, 26 (FIG. 2 ), and a hanger assembly 28. The housing 22 caninclude a light support portion 30 and a controller support portion 32adjacent to the light support portion 30. The light support portion 30can define a lighting receptacle 34 (FIG. 1 ) and a window 36 (FIG. 2 )disposed beneath the lighting receptacle 34. The first and secondlighting modules 24, 26 (FIG. 2 ) can be disposed within the lightingreceptacle 34 above the window 36 and can be configured to emit lightthrough the window 36, as will be described in further detail below.

The hanger assembly 28 can facilitate suspension of the light fixture 20above one or more plants (not shown) such that light emitted through thewindow 36 from the first and second lighting modules 24, 26 can bedelivered to the underlying plant(s) to stimulate growth. The hangerassembly 28 can include a pair of hanger supports 38 and a hangerbracket 40. The hanger supports 38 can be coupled to the housing 22 onopposing sides of the light fixture 20. The hanger bracket 40 can becoupled with the hanger supports 38 and can extend between the hangersupports 38 to facilitate suspension of the light fixture 20 from aceiling of the indoor grow facility. In one embodiment, as illustratedin FIGS. 1 and 2 , the hanger bracket 40 can have a cross-sectionalshape that is substantially J-shaped to facilitate selective hanging ofthe light fixture 20 from a beam or other elongated support member thatis provided along a ceiling of the indoor grow facility.

Referring now to FIGS. 3 and 4 , the housing 22 can include a main frame42 and a cover member 44 that overlies the main frame 42 and is coupledtogether with the main frame 42 via welding, adhesives, releasable tabs(not shown), fasteners (not shown), or any of a variety of suitablealternative permanent or releasable fastening arrangements. The mainframe 42 can include a bottom lighting wall 46 that defines the window36. As illustrated in FIG. 3 , the main frame 42 can include a bottomcontroller wall 48, and a plurality of sidewalls 50 that cooperate todefine a controller receptacle 52. The cover member 44 can include a lidportion 54 that overlies and covers the controller receptacle 52, asillustrated in FIG. 1 . The bottom controller wall 48, the sidewalls 50,and the lid portion 54 can form at least part of the controller supportportion 32 of the housing 22.

As illustrated in FIG. 4 , the first and second lighting modules 24, 26can each include a submount 56, 58, a plurality of light emitting diodes(LEDs) (e.g., 60 in FIG. 5 ), and a lens cover 64, 66. Referring to FIG.5 , the first lighting module 24 will now be discussed, but can beunderstood to be representative of the second lighting module 26. TheLEDs 60 can comprise surface mount LEDs that are mounted to the submount56 via any of a variety of methods or techniques commonly known in theart. The LEDs 60 can be any of a variety of suitable configurations thatare mounted directly or indirectly to the submount 56. The LEDs 60 cancomprise single color LEDs (e.g., capable of emitting only one color oflight such as white, red or blue), multi-color LEDs (e.g., capable ofemitting different colors such as white, red, and blue) or a combinationof both. The submount 56 can be formed of any of a variety of thermallyconductive materials that are suitable for physically and thermallysupporting the LEDs 60.

The lens cover 64 can overlie the submount 56 and the LEDs 60 and can becoupled with the submount 56 with fasteners 67 or any of a variety ofsuitable alternative coupling arrangements. The lens cover 64 caninclude a base substrate 68 that is substantially planar and a pluralityof optical lens elements 70 that protrude from the base substrate 68.Each of the optical lens elements 70 can be substantially aligned withrespective ones of the LEDs 60 and can be configured to redistribute(e.g., concentrate or disperse) the light emitted from the LEDs 60towards an area beneath the light fixture 20 (e.g., towards one or moreplants). In one embodiment, as illustrated in FIGS. 4 and 5 , each ofthe optical lens elements 70 can have an indented oval shape. However,the optical lens elements 70 can be any of a variety of suitablealternative shapes or combinations thereof for achieving a desiredredistribution of light emitted from the LEDs 60.

As illustrated in FIG. 5 , the LEDs 60 can each be aligned withrespective ones of the optical lens elements 70 such that the physicalcenter P and the focal center F are coaxial. In another embodiment, theLEDs 60 can each be slightly offset with respective ones of the opticallens elements 70 such that the physical center P and the focal center Fare non-coaxial. In one embodiment, the lens cover 64 can have a unitaryone-piece construction formed of a polycarbonate material and/orpolymethyl methacrylate (PMMA). It is to be appreciated, however, thatthe lens cover 64 can be formed of any of a variety of suitablealternative translucent or transparent materials that can protectunderlying LEDs from environmental conditions and can also accommodate aplurality of optical lens elements 70 for redistributing lighttransmitted from underlying LEDs.

The lens cover 64 can be spaced from the submount 56 such that the lenscover 64 and the submount 56 cooperate to define an interior 72therebetween. An encapsulating material 74 can be provided within theinterior 72 such that the encapsulating material 74 substantially fillsthe interior 72 and encapsulates the LEDs 60 therein. The encapsulatingmaterial 74 can be formed of an optically neutral (or enhancing)material that reduces optical loss in the interior 72 that mightotherwise occur without the encapsulating material 74 (e.g., if therewas air in the interior 72). In one embodiment, the interior 72 can befilled with enough of the encapsulating material 74 (e.g., filledentirely) to cause the interior 72 to be substantially devoid of airbubbles or other media that would adversely affect the optical integritybetween the LEDs 60 and the lens cover 64. The encapsulating material 74can also protect the LEDs 60 from environmental conditions that might beable to bypass the lens cover 64 such as a gaseous fluid (e.g.,greenhouse gas). In one embodiment, the encapsulating material 74 can bea silicone gel such as a methyl type silicone (e.g.,polydimethylsiloxane) or a phenyl-type silicone, for example, that has arefractive index of between about 1.35 and 1.6. It is to be appreciatedthat any of a variety of suitable alternative materials are contemplatedfor the encapsulating material 74.

The encapsulating material 74 can be substantially softer than the lenscover 64 (e.g., the encapsulating material 74 can have a hardness thatis less than a hardness of the lens cover 64). In one embodiment, theencapsulating material 74 can be a flowable material, such as a fluid orgel that can be injected or otherwise dispensed into the interior 72after the lens cover 64 is assembled on the submount 56. In anotherembodiment, the encapsulating material 74 can be coated onto the lenscover 64 and/or over the submount 56 and LEDs 60 prior to assembling thelens cover 64 on the submount 56.

Still referring to FIG. 5 , a protective coating 76 can be provided overan exterior surface 77 of the lens cover 64. The protective coating 76can be hydrophobic, oleophobic, and/or chemically resistant such thatthe exterior surface of the lens cover 64 is protected from harmfulenvironmental conditions that might otherwise adversely affect theoptical performance of the optical lens elements 70. The protectivecoating 76 can additionally or alternatively optically enhance thetransmission quality of the optical lens elements 70. In one embodiment,the protective coating 76 can be a thin-film inorganic material thatprotects against environmental conditions (e.g., chemical etching) andalso improves overall transmission quality of the optical lens elements70. The thin-film inorganic material can be between about 10 nm andabout 200 nm thick and can have a refractive index above about 1.49.Some examples of suitable thin-film inorganic materials include MgF2,CaF2, SiO2, Al2O3 and/or TiO2. Although the protective coating 76 isshown to be a single layer arrangement, it is to be appreciated that theprotective coating 76 can alternatively be a multi-layer arrangementthat is either homogenous (multiple layers of the same material) orheterogeneous (multiple layers of different material).

It is to be appreciated that the light emitted by the first lightingmodule 24 can conform to a lighting profile (e.g., range of color,overall distribution of light, heat profile) that is defined by thephysical configuration of the first lighting module 24 (e.g., the typesof LEDs 60 that are utilized (e.g., single color or multi color), thephysical layout of the LEDs 60, the optics provided by the optical lenselements (e.g., 70), the encapsulating material (e.g., 74), theprotective coating (e.g., 76), and the overall power consumption).Although various examples of the physical configuration of the firstlighting module are described above and shown in the figures, it is tobe appreciated that any of a variety of suitable alternative physicalconfigurations of the first lighting module 24 are contemplated forachieving a desired lighting profile.

Referring now to FIGS. 1 and 3 , a heat sink 78 can be disposed overeach of the first and second lighting modules 24, 26 and can beconfigured to dissipate heat away from the first and second lightingmodules 24, 26. The heat sink 78 can be formed of any of a variety of athermally conductive materials, such as aluminum or copper, for example.The heat sink 78 can be in contact with the submounts 56, 58 on anopposite side from the LEDs (e.g., 60). Heat generated by the LEDs(e.g., 60) can be transferred from the submounts 56, 58 to the heat sink78 and dissipated to the surrounding environment by a plurality of fins80. In one embodiment, a heat sink compound (not shown), such as thermalpaste, for example, can be provided between the submounts 56, 58 and theheat sink 78 to enhance the thermal conductivity therebetween. Althoughthe heat sink 78 is shown to be a unitary component that is providedover the first and second lighting modules 24, 26, it is to beappreciated that dedicated heat sinks can alternatively be provided foreach of the first and second lighting modules 24, 26.

Referring now to FIG. 3 , a controller 82 can be disposed in thecontroller receptacle 52 and can be configured to power and control thefirst and second lighting modules 24, 26. As illustrated in FIG. 1 , thelid portion 54 of the cover member 44 can overlie the controllerreceptacle 52 and the controller 82. The lid portion 54 can serve as aheat sink for the controller 82 and can include a plurality of fins 84to facilitate dissipation of heat from the controller 82. A heat sinkcompound (not shown), such as thermal paste, for example, can beprovided between the lid portion 54 and the controller 82 to enhance thethermal conductivity therebetween. The main frame 42 and the covermember 44 can each be formed of a thermally conductive material such asaluminum, for example. Heat from the first and second lighting modules24, 26 and the controller 82 can be transmitted throughout the housing22 to effectively supplement the cooling properties of the heat sink 78and the lid portion 54.

Referring now to FIGS. 1 and 2 , the housing 22 can define a passageway85 that extends between the light support portion 30 and the controllersupport portion 32 such that the first and second lighting modules 24,26 and the controller 82 are physically spaced from each other. Thepassageway 85 can be configured to allow air to flow between the lightsupport portion 30 and the controller support portion 32 to enhancecooling of the first and second lighting modules 24, 26 and thecontroller 82 during operation. In one embodiment, as illustrated inFIG. 3 , the housing 22 can comprise a plurality of rib members 86 thatextend between the light support portion 30 and the controller supportportion 32 to provide structural rigidity therebetween.

Referring now to FIG. 6 , the controller 82 can include a power supplymodule 88 and an LED driver module 90. The power supply module 88 can becoupled with the LED driver module 90, and the LED driver module 90 canbe coupled with each of the first and second lighting modules 24, 26(e.g., in parallel). The power supply module 88 can include a powerinput 92 that is coupled with a power source (not shown), such as an A/Cpower source, for delivering external power to the power supply module88 for powering the first and second lighting modules 24, 26. The powersupply module 88 can be configured to condition the external power fromthe power source (e.g., transform AC power to DC power) to facilitatepowering of the LEDs (e.g., 60). In one embodiment, the light fixture 20can be configured to operate at an input power of between about 85 VACand about 347 VAC (e.g., a 750 Watt load capacity).

The LED driver module 90 can include a control input 94 that is coupledwith a control source (not shown), such as a greenhouse controller, forexample, that delivers a control signal to the LED driver module 90 forcontrolling the first and second lighting modules 24, 26, as will bedescribed in further detail below. The LED driver module 90 can beconfigured to communicate according to any of a variety if suitablesignal protocols, such as BACnet, ModBus, or RS485, for example.

The power input 92 and the control input 94 can be routed to a socket 96(FIGS. 2 and 6 ) that is configured to interface with a plug (not shown)that can deliver the external power and control signals to the powersupply module 88 and the LED driver module 90, respectively. In oneembodiment, the socket 96 can be a Wieland-type connector, althoughother connector types are contemplated. It is to be appreciated thatalthough the power and control signals are shown to be delivered throughthe socket 96 (e.g., via the same cable), the light fixture 20 canalternatively include separate ports for the power and the controlsignal such that the power and the control signal are transmitted to thepower supply module 88 and the LED driver module 90 along differentcables.

The LED driver module 90 can be configured to control one or more of theintensity, color, and spectrum of the light generated by the LEDs (e.g.,60) as a function of time (e.g., a light recipe). The LED driver module90 can control the light recipe of the first and second lighting modules24, 26 independently such that the first and second lighting modules 24,26 define respective first and second lighting zones that areindependently controllable within the lighting environment. The lightrecipes of the first and second lighting zones can accordingly betailored to accommodate the lighting requirements of plants that areprovided within the lighting environment. For example, when the plantsprovided in each of the first and second lighting zones are the same (orhave similar lighting requirements), the respective light recipes forthe first and second lighting modules 24, 26 can be the same to providea substantially uniform lighting environment between the first andsecond lighting zones. When a group of plants provided in the firstlighting zone has a different lighting requirement from a group ofplants provided in the second lighting zone, the respective lightrecipes for the first and second lighting modules 24, 26 can be tailoredto accommodate the different lighting requirements between the groups ofplants. In one embodiment, the first and second lighting modules 24, 26can have unique addresses such that the control signal can assignseparate lighting recipes to each of the first and second lightingmodules 24, 26 (via the LED driver module 90) based upon their uniqueaddresses. It is to be appreciated, that although the LED driver module90 is described as being configured to control the light recipe of eachof the first and second lighting modules 24, 26, the LED driver module90 can additionally or alternatively be configured to control any of avariety of suitable alternative variable lighting features of the firstand second lighting modules 24, 26 (e.g., any lighting feature that canbe controlled in real time with a control signal).

The first and second lighting modules 24, 26 can be self-contained,stand-alone units that are physically separate from each other. As such,the physical configuration and variable lighting features of each of thefirst and second lighting modules 24, 26 can be individually selected toallow the first and second lighting zones to be customized to achieve adesired lighting environment. In one embodiment, the first and secondlighting modules 24, 26 can be exchanged with different lighting modulesduring the life cycle of a plant to optimize the lighting environmentfor the plant throughout its life cycle.

The foregoing description of embodiments and examples has been presentedfor purposes of illustration and description. It is not intended to beexhaustive or limiting to the forms described. Numerous modificationsare possible in light of the above teachings. Some of thosemodifications have been discussed and others will be understood by thoseskilled in the art. The embodiments were chosen and described forillustration of various embodiments. The scope is, of course, notlimited to the examples or embodiments set forth herein, but can beemployed in any number of applications and equivalent devices by thoseof ordinary skill in the art. Rather, it is hereby intended that thescope be defined by the claims appended hereto. Also, for any methodsclaimed and/or described, regardless of whether the method is describedin conjunction with a flow diagram, it should be understood that unlessotherwise specified or required by context, any explicit or implicitordering of steps performed in the execution of a method does not implythat those steps must be performed in the order presented and may beperformed in a different order or in parallel.

What is claimed is:
 1. A light fixture for an indoor growing facility,the light fixture comprising: a housing; and a lighting module at leastpartially disposed in the housing, the lighting module comprising: asubmount; a plurality of light emitting diodes coupled with thesubmount; a lens cover comprising a base substrate, a plurality of lenselements protruding from the base substrate, and an exterior surface,the lens cover overlying the plurality of light emitting diodes and thesubmount such that the lens cover and the submount define an interiortherebetween; and an encapsulating material that substantially fills theinterior and encapsulates the plurality of light emitting diodes,wherein: the lens cover has a first hardness; the encapsulating materialhas a second hardness that is less than the first hardness; and eachlight emitting diode of the plurality of light emitting diodes isaligned with respective lens elements of the plurality of the lenselements.
 2. The light fixture of claim 1 wherein: each light emittingdiode of the plurality of light emitting diodes comprises a physicalcenter; each lens element of the plurality of lens elements comprises afocal center; and the physical center of each light emitting diode ofthe plurality of light emitting diodes is aligned with the focal centerof the respective lens elements of the plurality of the lens elements.3. The light fixture of claim 1 wherein: the housing comprises a firstportion and a second portion; the second portion defines a window; andthe light fixture further comprises a controller at least partiallydisposed within the first portion.
 4. The light fixture of claim 3wherein the housing defines a passageway between the first portion andthe second portion.
 5. The light fixture of claim 4 further comprising aplurality of rib members that extend between the first portion and thesecond portion and are at least partially disposed in the passageway. 6.The light fixture of claim 1 wherein the second hardness is a Shore A ofless than
 70. 7. The light fixture of claim 6 wherein the encapsulatingmaterial comprises a silicone gel.
 8. The light fixture of claim 1wherein the lens cover is formed of a polycarbonate or polymethylmethacrylate.
 9. A light fixture for an indoor growing facility, thelight fixture comprising: a housing comprising a first portion and asecond portion, the second portion defining a window; a controller atleast partially disposed within the first portion; a first lightingmodule at least partially disposed in the second portion; and a secondlighting module at least partially disposed in the second portionadjacent to the first lighting module, wherein each of the firstlighting module and the second lighting module comprises: a submount; aplurality of light emitting diodes coupled with the submount andconfigured to project light through the window; a lens cover comprisinga base substrate, a plurality of lens elements protruding from the basesubstrate, and an exterior surface, the lens cover overlying theplurality of light emitting diodes and the submount such that the lenscover and the submount define an interior therebetween; and anencapsulating material that substantially fills the interior andencapsulates the plurality of light emitting diodes, wherein: the lenscover has a first hardness; the encapsulating material has a secondhardness that is less than the first hardness; the first lighting moduleand the second lighting module are physically independent from eachother; and each light emitting diode of the plurality of light emittingdiodes is aligned with respective lens elements of the plurality of thelens elements.
 10. The light fixture of claim 9 wherein: each lightemitting diode of the plurality of light emitting diodes comprises aphysical center; each lens element of the plurality of lens elementscomprises a focal center; and the physical center of each light emittingdiode of the plurality of light emitting diodes is aligned with thefocal center of the respective lens elements of the plurality of thelens elements.
 11. The light fixture of claim 9 wherein the secondhardness is a Shore A of less than
 70. 12. The light fixture of claim 11wherein the encapsulating material comprises a silicone gel.
 13. Thelight fixture of claim 9 wherein the lens cover is formed of apolycarbonate or polymethyl methacrylate.
 14. The light fixture of claim9 wherein the housing defines a passageway between the first portion andthe second portion.
 15. The light fixture of claim 14 further comprisinga plurality of rib members that extend between the first portion and thesecond portion and are at least partially disposed in the passageway.16. A light fixture for an indoor growing facility, the light fixturecomprising: a housing comprising a first portion and a second portion,the second portion defining a window; a controller at least partiallydisposed within the first portion; and a lighting module at leastpartially disposed in the second portion, the lighting modulecomprising: a submount; a plurality of light emitting diodes coupledwith the submount and configured to project light through the window; alens cover comprising a base substrate, a plurality of lens elementsprotruding from the base substrate, and an exterior surface, the lenscover overlying the plurality of light emitting diodes and the submountsuch that the lens cover and the submount define an interiortherebetween; and a silicone gel that substantially fills the interiorand encapsulates the plurality of light emitting diodes, wherein: thelens cover has a first hardness; the silicone gel has a second hardnessthat is less than the first hardness; and each light emitting diode ofthe plurality of light emitting diodes is aligned with respective lenselements of the plurality of the lens elements.
 17. The light fixture ofclaim 16 wherein: each light emitting diode of the plurality of lightemitting diodes comprises a physical center; each lens element of theplurality of lens elements comprises a focal center; and the physicalcenter of each light emitting diode of the plurality of light emittingdiodes is aligned with the focal center of the respective lens elementsof the plurality of the lens elements.
 18. The light fixture of claim 16wherein the lens cover is formed of a polycarbonate or polymethylmethacrylate.
 19. The light fixture of claim 16 wherein the housingdefines a passageway between the first portion and the second portion.20. The light fixture of claim 19 further comprising a plurality of ribmembers that extend between the first portion and the second portion andare at least partially disposed in the passageway.